Carb Sources: Breaking Down the Breakdown



When it comes to nutrition, one would reasonably argue that not all macro sources are created equal. In this post, we will focus on carbohydrates. Regardless of whether you follow a “clean eating” type of diet, or a more macro-based approach, not all carbs are the same. Let’s discuss the different types of carbs, what they do, and when you will want to ingest them.

What’s a Carbohydrate?

For starters, we will define a carbohydrate as a biomolecule and macronutrient, which weighs in at approximately 4 calories per gram. Responsible for everything from energy production in the body to keeping us regular via fiber, carbohydrates are an incredibly important macronutrient. While carbs are found in most plant products (grains, fruits, legumes, etc.), they can also be found in dairy products, as well.

Carbohydrates are generally broken down into two main (but somewhat ambiguous) classes, based on their chemical structure: simple or complex. If you want to be a real stickler about classification, you can group them by the types of sugar they break down into: monosaccharides/disaccharides for simple, or polysaccharides for complex, by their glycemic index, or even by their insulin index. More on that later.

In terms of some common examples, simple carbohydrates will include the sugars naturally found in fruits, vegetables, milk products, and any sugar added during processing and refining of many pre-packaged products. Complex carbohydrates include most whole grain products (pasta, bread, cereal, oats), starchy vegetables such as potato, and legumes.

A Few Other Noteworthy Terms/Concepts:

Upon consumption, the body breaks carbohydrates down into its constituent sugars for energy. Any excess sugar is stored in the muscles and liver, for later consumption, as glycogen, or if not used, can be stored as fat in the body.

Glycogen is the stored form of glucose in the body. In any physical activity, stored glycogen delivers quick fuel to the body.

A whole, unprocessed carb is a carb or food that has been minimally altered, with most of its nutrients intact. Think sweet potatoes, fruits, and legumes.

A refined carb is a carb that has been processed, stripping the item of its fiber, and other valuable nutrients.  Think white rice/bread, fruit drinks, and white flour.

While the common school of thought insisted that “brown” carbs (rice, pasta, bread) were better than their refined/white counterparts (white rice, semolina pasta, white bread), recent research has shown that they are essentially the same, from a nutritional standpoint, with their “whole grain” or brown versions providing just a bit more fiber.

The Glycemic Index is a relative ranking of the carbohydrates in foods, based on how they impact blood glucose levels. Carbohydrates with a value less than 55 are slower to digest, causing a slower rise in blood glucose and insulin levels.

The Insulin Index is similar to the glycemic index, only measuring blood insulin levels, and not blood glucose levels.

The Impact of Each Type of Carb:

When discussing which carb sources do what to the body, we are obviously looking primarily at how slowly/quickly that carb will digest, and what impact it will have on an individual’s insulin levels. The goal overall for any individual (and especially athletes) would be to ingest enough carbs (from a myriad of sources) to be stored as glycogen to fuel activity and feed the muscles, without being stored as excess fat.

Generally speaking, any simple or refined carbohydrate will spike blood glucose and insulin, and will provide fast energy with a relatively low level of lasting power. Conversely, complex carbohydrates will digest more slowly, providing a more even (albeit lower) energy level, over a longer period of time.

Nutrient Timing – When to Eat What:

From a weight training perspective, it is especially beneficial to fuel the body with carbohydrates, in accordance with your training, via nutrient timing. A complex carbohydrate about an hour before your workout will fuel you throughout your session, while a simple/refined carbohydrate immediately after will flood your depleted muscles with the glucose they need to grow. A lot of bodybuilders choose to have candy and high sugar items immediately before/after their workouts, for not only the energy, but the glucose spikes to the muscles when they need it most.

From a nutritional standpoint, whole and complex carbohydrates are the most beneficial, as they provide the body with fiber, nutrients, energy, and satiety. These should be the bulk of your carbohydrate intake. Try to keep the added sugars to a minimum, unless you know you are going to put those to work for the muscles.  

Not all carbs are created equal, from a chemical and nutritional standpoint. By choosing your carb sources smartly, and timing your intake, you can magnify your results, almost instantly.